The present invention relates, in general, to electronics, and more particularly, to methods of forming semiconductor devices and structure.
In the past, the semiconductor industry utilized various methods and structures to form power supply controllers that would assist in regulating an output voltage to a desired value. In some power supply configurations, two transistors were connected in a stacked configuration or half-bridge circuit configuration in order to drive an inductor and form the output voltage. Each of the two transistors in the half-bridge circuit were driven by separate transistor drivers. The high side driver generally operated from a higher supply voltage than the low side driver. The higher power supply voltage often was referred to as a boost voltage and was developed by a bootstrap circuit from the voltage at a common node connection between the high side and low side transistors. In some operating modes, the two transistors may not be switched for a period of time. These periods of non-switching were often referred to as burst mode or cycle-skipping. During such time periods, the value of the boost voltage often decreased which caused inefficient operation of the power supply system.
Accordingly, it is desirable to have a power supply controller that can provide power to the high side driver during time periods that the power switches are not switching.